1. Technical Field
The technique described herein relates generally to medical imaging.
2. Background of the Related Art
Medical imaging is the technique used to create images of the human body or parts thereof for clinical purposes (medical procedures that seek to reveal, to diagnose or to examine disease) or medical science (including the study of normal anatomy and physiology). Computer tomography (CT) and magnetic resonance imaging (MRI) are two of the most common approaches. These techniques generate a set of individual 2D images that can be displayed in a 3D visualization as a “volume dataset.”
In the fields of Radiology and Interventional Cardiology, a particularly important aspect of diagnosing and treating the patient is being able to accurately image the arteries or vessels of the body. Typically, the patient will be given an X-ray CTscan, which creates a collection of consecutive image slices that form a volume of patient data when stacked, or rendered electronically. Several known rendering methods that allow CT data to be viewed have emerged over the years. One of the methods, Maximum Intensity Projection (MIP), fires rays through a volume from a position and a direction, and as it samples each pixel, it looks for the pixel with the greatest intensity along the ray. This maximally intense pixel value is plotted to the screen directly for visualization by a user. A collection of these pixels forms an image where dense structures are able to be seen through less dense structures without regard to the depth of these structures.
MIP-based rendering can be very useful in many circumstances, for example, to see a contrasted artery even when the artery is surrounded by muscle or fat. The problem with a MIP-based approach to viewing an artery, however, is that, while the contrast can easily be seen, the vessel wall is more difficult to discern. It would be very beneficial to be able to determine the diameter of the open area of the artery in relation to the vessel wall when MIP-based rendering is used.